Electrical time switch



n. 18 192 7 c. w. BROWN ELECTRICAL TIME SWITCH Filed August 30. 1922 nmw me r w s M c A TTOR/VE Y8 Patented Jan. 18, 1927.

UNITED STATES CHARLES WESLEY BROWN, 01' MOUNT VERNON, 7mm.

ELECTRICAL rmn SWITCH.

Application and August so, 1022. lerlsl 11b. 1115,1117.

This invention relates to an electrical time switch and has particularreference to one which involves the thermostatic control.

An object of the invention resides in the provision of means whereby anelectrical time switch can be used in conjunction with the ordinaryswitch so that a person may turn off the ordinary switch, leaving thetime switch closed, without worrying about the circuit remaining closedbeyond a predetermined eriod of time.

Another 0 ject resides in the provision of means whereby a time switchcan be readily adapted for use in connection with the ordinary types ofswitches, involving a minimum amount of substitution and alteration toadapt it to use.

A further object resides in the provision of means whereb a time switchincorporated with the or inary switch can be operativel employedtherewith or disconnected there rom at will. I

A still further object resides in the particular construction andarrangement of parts which are hereinafter described and claimed andshown in the accompanying drawings.

The lnvention is illustrated in the drawings, of which- Figure 1 is aside elevation of a form of my switch.

Fig. 2 is an inverted plan view thereof.

Fig. 3 is a transverse section taken on the line 3-3 of Fig. 1.

Fi 4 is a transverse section taken on the line 4-4 of Fig. 1.

Fig. 5 is a longitudinal vertical section through a modified form ofswitch.

Fig. 6 is an inverted plan view thereof with the bottom late removed.

The forms of t e invention shown in the drawings are referred forms,although it is understood t at modifications in the construction andarrangement of the parts and in the character of the materials used maybe adopted without departing from the spirit of the invention.

As illustrated in the drawings, which concern two preferred forms of myinvention, and referring first to Figs. 1 to 4, incluslve, illustrativeof one of these forms, the invention therein disclosed has reference toa switch unit involving a plu 1 and a socket 2 mechanically connected ya plate 3. One end of this plate 3 is connected electrically to theshell 4 of the socket 2. The

other end of this pla however is on] embedded in suitable insulatingmaterial 5 within the plu 1 and is not itself electricallsy colnrlxecgedt GITItO. The central contacts an 0 tie soc st and In rexectivel areconnected by a wire 8, i|s own l n Fig. 1.

ounted on the plate 3, referably adjacent one end thereof near 51ssocket 2, are two push buttons 9 and 10. These buttons are connected tothe ends of springs 11 and 12, the other ends of which are connected tothe plate or suitably embedded in the insulation 5. The tendenc of thesea 1s to keep the buttons in t eir retract position, shown in Fig. 1.

Also, suitably su ported in the insulating material 5 within t e shell13 of the plug 1 are arpair of switch' plates 14 and 15 as shownparticularly in Fig. 2. One of these plates 14 is wrapped with wire 16,preferably fine heating wire. This wire is, preferably, on plate 14wrapped, preferably, on a suitable insulating material (not shown). Theeffect of current pass' through this fine wire is to heat the switcplate 14 and cause it to bend, it being fastened at one end as abovementioned. The

free end 17 of this plate 14 is somewhat bent and is adapted normally tolie above the end of the plate 15 and in electrical contact therewith.Referring to the switch plate 14 as shown n F gure 2 and a similar plateas shown in Flgure 6, it will be noted that the ends of these two platesbeyond the lap of the heat coil 13 and 34 respectively are bent so thatthe. ends of these two lates will act as latches in the manner descriWhen current is applied to the heating coil the heat is naturallytransferred to the plate and effects the whole length of the same. Thusthe heat not only effects the straight portion but is conductivelytransmitted to the curved portion. Further the fact that the lates areformed of spring material an are curved will cause said plates whenheated to straighten out and it is this straightening out effect whichproduces the action described.

As noted particularly in Figs. 1 and 2, the shell 13 of plug 1 isconnected by a wire 18 to the heatlng wire 16 and also by a wire 19 to alatch plate 20. The other end of the heating wire 16 is connectedelectrically to the switch plate 14, and the other switch plate 15 isconnected by a wire 21 to the plate 3.

Tne plate 15 is provided with an apertured seat 22 in which the lowerend of the push button 10 is adapted to be disposed, the lower end ofthis button being in the form of a netallic head 23 having a laterallatching inger 24 thereon, as shown particularly in Fig. 4. As thisbutton 10 1s depressed, the head 23 engages in the seat on the switchplate 15 to depress it and cause the disenga ement of its end with theend of the switch plate 14. This disengagement opens the circuit betweenthe two plates, where by current ceases to exist in the heating wire 16.As the button 10 is depressed, the latching finger on the lower endthereof Wlll. engage with the latching plate 20, the natural position ofwhich is to dispose it in the path of the head 23.

The depression of the button 9 will engage the outer end 25 of thelatching plate 20 to move it laterally and disengage it from thelatching finger 24. This disengagement permits the button 10 to move tonormal position. It will be noted that during the depressed condition ofthe button 10, the head 23, which is made of conducting material,electrically and mechanically forms a bridge between the latching plate20 and the switching plate 15.

In other words, when the button'lO is depressed, it is provided withmeans whereby its depression is maintained; whereas, when the button 9is depressed and released it will immediately spring back into normalposition. Furthermore, when the button 9 is depressed, it acts torelease the button 10.

As shown in Figs. 5 and 6, another form of my invention involves asuitable base 26 on which a, preferably, metallic casing 27 is disposed,having a portion 28 of insulating material at one end thereof. Embeddedin this insulating material at their ends are a pair of switch plates 29and 30. The end of the plate 30 is curved and is provided with a camsurface 31 adapted to lie in the path of the end 32 of the plate 29. Abutton 33 is mounted on a casing 27 and when depressed against the plate29 forces it beneath the plate 30 and, at the same time, forcing thisplate to one side will permit it to slide back over the top of the endof the plate 29 whereby this latter plate will be held depressed and inengagement with the end 31 of the plate 30. As above described, aheating wire 34 is wrapped around the plate 30, and when the two platesare in engagement current passes throu h this heating wire and causesthe deflection of the plate 30 in a direction to release the plate 29after a suitable interval of time. Wires 35 may be properly connected tothe heating wire 34 and the plate 29 whereby this switch may beconnected circuit.

misuse can be traced: from the central contact 7,.

through the wire 8, through the central contact 6, through the circuitand back to the shell 4, through the shell 4, throu h the plate 3; fromthe plate 3 through t e wire 21 and the switching plate 15, thencethrough switch plate 14 engaged by the switching plate 15 through theheating wire 16, through wire 18, back to the shell 13 of the plug 1. Inother words, during this time the current is passing through the heatinwire 16. This heating wire will cause a c leflection of the switchingplate 14 whereby it will, after a certain perlod of time, becomedisengaged from the switch plate 15, thus breaking the main circuit. Ifit is desired, however, to eliminate this thermostatic action, it ismerely necessary to depress the button 10. This button 10 will disengagethe switch plates 14 and 15 in the manner above described and, at thesame time, will bridge the circuit between the late 15 and the latchplate 20 to establish t e following circuit: from central contact 7,through wire 8, to central contact 6, out on the circuit, and back toshell 4, through plate 3, through wire 21, through plate 15, across thehead 23 of the button 10 to latch plate 20, through wire 19 to the shell13 of plug 1. This circuit will be maintained permanently as long as thebutton 10 is depressed, there being no thermostatic action involved. Tobreak this circuit, however, it is merely necessary to depress thebutton 9 momentarily. This forces the latch plate 20 to one side,releasing the plate from engagement with the latching finger 24 on thehead 23 of the button 10, permitting the button to return to normalposition, whereupon the switching plate 15 reengages with the end of theswitching plate 14 and thereby reestablishes the thermostatic circuit.This device may be used in series with an ordinary socket or may be usedin parallel with another switch. 4

In the operation of the device shown in Figs. 5 and 6, it is apparentthat this device can be used in series with any switch but when inseries with a switch will automatically open after being closed for adefinite period of time. It is referable to use this modification inparalle with another switch, and when this invention is to be put intooperation it is necessary to open the switch with which it is in aralleland then depress the button 33, whic will close the thermostatic switchplates and they will remain closed until the effect of the heat on theone switch plate will cause it to be deflected sufii-- ciently far forit to become disengaged from the other switch plate, whereupon thecircuit is open.

What I claim is 1. An electrical time switch adapted to be placed inmultiple with an ordinar switch, which includes a pair of switc membersnormally engaged, a heating coil on one of said members electricallyconnected thereto to receive current therefrom and eiiect the heatin ofsaid member whereby its distortion will disengage it from another switchmember after a given interval of time, means for disengaging saidmembers, means for holding said disengaging means in its operativeposition, and means for releasing said holding means.

2. An electrical time switch, which includes a pair of switching membersnormally engaged, a heating coil on one of said members electricallyconnected thereto to effect its distortion by heating whereby it becomesdisengaged from the other member after a given interval of time,independent means for disengaging said members at will, means on saiddisengaging means for establishin a circuit as a substitute for thecircuit t rough the switch member, means for holding said disengagingmeans in its operative osition, and means for releasing said hol ingmeans at will.

3. An electrical time switch, which includes a pair of flexibleswitching plates adapted to be engaged normally, a heating coil on oneof said plates connected. thereto and receiving current whereby the heateffeet will cause a distortion of the switching plate and effect itsdisengagement from the other switching plate after a given interval oftime, a button to be depressed, a head on said a button to engage withone of said plates and disengage it from the other of said plates, alatch late, said head adapted when depressed to orm a conductive pathbetween the depressed switching plate and the latch plate, circuitconnections establishing an independent circuit between the depressedswitching plate and the latch plate as a substitute for the circuitbroken, means on the head to be engaged with the latch plate to hold thedisengaging button in its operative position, a second buttondepressible to release the latch plate from the first button, and meansfor moving both of said buttons to normal position when released wherebythe independent circuit is open and the'normal circuit through theswitch plate 00 is reestablished.

CHARLES WESLEY BROWN.

